Let us start with how and why. Recommendations that people reduce their red meat intake have been around for years. The WHO deemed this an important topic for further inquiry based off of previous studies concerning a link between meat and cancer, and the fact that global meat consumption has been steadily increasing. The IARC brought together scientists from ten different countries to look over previous epidemiological studies from various countries on the link between red meat and cancer. In particular, the IARC put the most weight on research that used a method known as a prospective cohort study, in which participants are followed throughout the study. For example, researchers looking at a link between meat consumption and bladder cancer recruited two different groups of people and sent them questionnaires every two and four years to gauge both their overall health and their dietary habits, respectively.

To be clear, the WHO considers red meat to include beef, veal, pork, lamb, mutton, horse, and goat. Processed meat is “meat that has been transformed through salting, curing, fermentation, smoking, or other processes to enhance flavour or improve preservation,” so it includes hot dogs, ham, sausages, etc.

The verdict? These researchers classified red meat as “probably carcinogenic to humans” and processed meats as “carcinogenic to humans.” The link between meat and cancer was mostly for colorectal cancer, but red meat was also found to be associated with pancreatic and prostate cancers. It is still not known exactly what methods of cooking meat are the safest (high temperature cooking may be linked with the formation of carcinogenic substances) or exactly how much meat is “safe to eat.” It seems that for every 50 gram portion of processed meat eaten daily, the risk of colorectal cancer increasesby about 18%.

What this study means is that we should reduce consumption, not stop eating meat all together. As Dr. Christopher Wild, director of the IARC, says, red meat has nutritional value. This research is something to think about in the future when planning your diet; the IARC believes that it may be useful information in future dietary policies and recommendations.